Control for artificial arms and legs



J. R. B. NORFOLK.

CONTROL FOR ARTIFICIAL ARMS AND LEGS.

APPLICATION FILED AUG. I8. I920.

1 88,524, Patented Aug. 23 1921.

UNITED STATES,

JOSEPH R. B. NORFOLK, OF JESSUPS, MARYLAND.

OON'I'ROL FOR ARTIFICIAL ARMS AND LEGS.

Specification of Letters Patent.

Patented Aug. 23, 1921.

' Application vfiled August 18, 1920. Serial No. 404,479.

To all whom it may concern Be it known that I, JosnrH R. B. Non- :FoLK, a citizen of the United States, residing at Jessups, in the county of Anne Arundel and State of Maryland, have invented certain new and useful Improvements in Controls for Artificial Arms and Legs, of which the following is a specification.

My present invention relates to means for controlling movements of artificial members such as arms and legs. Its principal objects are to improve the efiiciency of such controls and to provide for greater comfort to the wearer of the artificial member under certain conditions, and to do so by simple and readily operable means while maintaining the operative relation of the control in service to the artificial limb.

In the accompanying drawings, which form a part of this specification, Figure 1 is a face view of end portions of two sections of a control strap or tape with an intermediate adjusting device in its controllengthening condition; Fig. 2 is an edge view of the parts of Fig. 1; Figs. 3 and 4 are views respectively similar to Figs. 1 and 2 but showing the connection device in its control-shortening position; Fig. 5 is a perspective of the swinging part of the connection device; and Fig. 6 shows one applica tion of the device to a control strap for an artificial leg.

As is well understood in the art, the move ments of the artificial limb are often controlled by means of a strap, usually in the form of a fabric tape, which is secured at one end to an o oerative part of the artificial member, the ot 1er end of the strap terminating in a loop which passes over the wearers shoulder. The length of this control strap is such that by lifting his shoulder the operator can draw firmly upon the strap or tape and provide motion which operates the leg or arm as the case may be. Illustrations of such controls and their general mode of operation may be found in my Patent No. 1,293,885 of February 11, 1919 on artificial limbs, and in my allowed copending application, Serial No. 302,658 filed June 9, 1919 on artificial legs.

In such controls an ordinary buckle is sometimes provided for adjusting its length to suit the general requirements of the particular wearer of the device. Adjustments by means of the ordinary buckle may be made from time to time as occasion sugsituations, for instance in a leg device where the wearer is about to go upstairs, it is desirable to shorten the control materially so as to render the pull by the shoulder upon the strap more firm and positive, through the taking up of temporarily inducedslack, than is called for in the ordinary operation of walking, and these improvements have as a specific object the provision of a control which may be readily and easily shortened and lengthened as required by particular exigencies of service, or for the comfort of the wearer, and without putting the artificial limb out of service.

In these drawings the end portion 10 of the control strap or tape is to be understood as leading to the shoulder loop mentioned while the fragment 11 thereof leads tothe artificial member the movements of which are to be controlled. To the strap part 10 I secure an eye member 12 consistmg of a metallic plate having a slot-like opening at 13 through which the tape passes and is fastened upon itself as by stitching, thereby holding the plate 12 securely at the end of the section 10 of the tape. To the section 11 of the tape is similarly secured the bow or yoke 14 having a pair of side members 15 apertured at 16 to form bearings for the plntles 17 of the swinging camlike device 18.

This swinging or rocking member 18 includes the cross bar 19, the finger lever 20 and the loop-shaped part 2].. The plate or eye member 12 has a slot-like opening or eye 23 through which the loop-shaped part 21 passes. The two tape ends 10 and 11 are therefore joined and the control made continuons by this intermediate adjusting de vice comprising the plate 12, the swinging member 1.8 and the yoke member 1 1-.

From the edge views it will be clearly seen that the distance from the axis of rocking movement of the part 18, namely, the axis defined by the pintles 17, to the ends respectively of the loop part 21 differs. hen the oar-ts are in their relative positions as shown y Figs. 1 and 2 what may be termed the long end portion of the loop 21 is interposed between the eye 23 and the axis of rocking movement defined by the pintles 17 When der the shirt of the wearer it is a simple and easy matter for him to operate the finger piece through the shirt, and according to i theseimprovements he is therefore enabled to increase and decrease the'eifective length of the control for particular movements from time to time or, should he find that 0W- ing to conditions of adjustment of the stump in the socket of the artificial member the p an opportunity offers for makingthe more control is effectively too long or tooshort for comfort, an adjustment may be made with the device of these improvements until permanent adjustment desired, which can be done b the ordinary buckle hereinabove referre to where the device is provided with that feature. i V

In my practice the parts 12, 14 andl 8 are of metal. The strap or tape portions may be of the usual construction.

" While I have herein illustrated and described a simple and advantageous form ofmy novel control reference should be had to the appended claims to determine the scope co'ntrol while maintaining the operative relation of the control in service to the artifi cial limb.

2. In a control for artificial limbs, the combination with control strap sections, of an intermediate device including a handoperable movable member for readily increasing and decreasing the effective length of the'control while maintaining the operative relation of the control in service to the artificial limb.

3. In a control for artificial limbs, the combination with two control strap sections, of an eye member secured to one section, a yoke member secured tothe other section, and a rocking member mounted on the yoke member, said rocking member including a loop part passing through the eye of the eye member, said loop part having a relatively long end portion and a relatively short end portion with respect to the axis of rocking movement.

JOSEPH R. B. NORFOLK.

Attest:

WALTER R. HEATH. 

